From 0e18cefe3857b35b90fa1bfb2c5edb7dd8ad2866 Mon Sep 17 00:00:00 2001 From: Andrew Gregory Date: Wed, 9 Jul 2014 22:47:50 -0400 Subject: filelist_intersection: manually compare paths Prevents the need to modify paths, removing strndup as an unchecked point of failure, and lengths only need to be calculated if the paths match. Also removed an old comment regarding directory/symlink compatibility. Signed-off-by: Andrew Gregory Signed-off-by: Allan McRae --- lib/libalpm/filelist.c | 56 ++++++++++++++++++++------------------------------ 1 file changed, 22 insertions(+), 34 deletions(-) diff --git a/lib/libalpm/filelist.c b/lib/libalpm/filelist.c index 2d2426c5..c41989ca 100644 --- a/lib/libalpm/filelist.c +++ b/lib/libalpm/filelist.c @@ -61,6 +61,23 @@ alpm_list_t *_alpm_filelist_difference(alpm_filelist_t *filesA, return ret; } +static int _alpm_filelist_pathcmp(const char *p1, const char *p2) +{ + while(*p1 && *p1 == *p2) { + p1++; + p2++; + } + + /* skip trailing '/' */ + if(*p1 == '\0' && *p2 == '/') { + p2++; + } else if(*p2 == '\0' && *p1 == '/') { + p1++; + } + + return *p1 - *p2; +} + /* Returns the intersection of the provided two lists of files. * Pre-condition: both lists are sorted! * When done, free the list but NOT the contained data. @@ -70,52 +87,23 @@ alpm_list_t *_alpm_filelist_intersection(alpm_filelist_t *filesA, { alpm_list_t *ret = NULL; size_t ctrA = 0, ctrB = 0; + alpm_file_t *arrA = filesA->files, *arrB = filesB->files; while(ctrA < filesA->count && ctrB < filesB->count) { - int cmp, isdirA, isdirB; - char *strA, *strB; - - isdirA = 0; - strA = filesA->files[ctrA].name; - if(strA[strlen(strA)-1] == '/') { - isdirA = 1; - strA = strndup(strA, strlen(strA)-1); - } - - isdirB = 0; - strB = filesB->files[ctrB].name; - if(strB[strlen(strB)-1] == '/') { - isdirB = 1; - strB = strndup(strB, strlen(strB)-1); - } - - cmp = strcmp(strA, strB); + const char *strA = arrA[ctrA].name, *strB = arrB[ctrB].name; + int cmp = _alpm_filelist_pathcmp(strA, strB); if(cmp < 0) { ctrA++; } else if(cmp > 0) { ctrB++; } else { - /* TODO: this creates conflicts between a symlink to a directory in - * one package and a real directory in the other. For example, - * lib -> /usr/lib in pkg1 and /lib in pkg2. This would be allowed - * when installing one package at a time _provided_ pkg1 is installed - * first. This will need adjusted if the order of package install can - * be guaranteed to install the symlink first */ - /* when not directories, item in both qualifies as an intersect */ - if(! (isdirA && isdirB)) { - ret = alpm_list_add(ret, filesA->files[ctrA].name); + if(strA[strlen(strA) - 1] != '/' || strB[strlen(strB) - 1] != '/') { + ret = alpm_list_add(ret, arrA[ctrA].name); } ctrA++; ctrB++; } - - if(isdirA) { - free(strA); - } - if(isdirB) { - free(strB); - } } return ret; -- cgit v1.2.3-70-g09d2